Placer-mining machine.



No. 769,489- PATENTED SEPT. 6, 1904. N. W. PULSIFER. PLACER MINING MACHINE.

APPLICATION FILED APR. 16, 1903. NO MODEL- 3 BHBETBSHEET 1.

YHIIIIIIN" illi No. 769,489. PATENTED SEPT. 6, 1904.

N. W. PULSIFER. PLACER MINING MACHINE.

APPLICATION FILED APR.16, 1903. N0 MODEL. 3 SHEETS-SHEET 2.

No. 769,439. PATENTED SEPT. 6, 1904. N. W. PULSIFER.

PLACER MINING MACHINE. APPLIOATION FILED APB. is, 1903. N0 MODEL.

3 SHEETSSHEET 3.

UNITED STATES Patented September 6, 1904;.

PATENT OFFICE.

PLACER-MINING MACHINE.

SPECIFICATION forming part of Letters Paten N 0. 769,489, dated September 6, 1904.

Application filed April 16, 1903. Serial No. 152,852. (No model.)

To (tZZ whont it may concern:

Be it known thatLNATHANIEL IV. PULSIFER, a citizen of the United States,residing at Philadelphia, county of Philadelphia, and State of Pennsylvania, have invented a certain new and useful Improvement in Placer-Mining Machines, of which the following is a specification.

My invention relates to a new and useful improvement in placer-mining machines, and has for its object to provide a machine of this character which will be simple, durable, and extremely eflicient, the entire combination being so constructed as to render it both compact and durable and easily taken down and set up when desired.

\Vith these ends in view this invention consists in the details of construction and combination of elements hereinafter set forth and then specifically designated by the claim.

In order that those skilled in the art to which this invention appertains may understand how to make and use the same, the construction and operation will now be described in detail, referring to the accompanying drawings, forming a part of this specification, in which Figure 1 represents a longitudinal vertical section through the entire machine; Fig. 2, a side elevation of the same; Fig. 3, a section taken on the line 3 3 of Fig. 2; Fig. 4:, a section taken on the line 4 et of Fig. 2.

A represents the hopper, which is held at the desired height by suitable framework, and the gravel is introduced in this hopper directly from the digging-s by derrick, buckets, or conveyer and falls directly upon the grizzly B. This grizzly consists of an inclined grating or perforated plate C, and arranged below the grating or plate C is a chute arranged upon the same incline as the plate, and all of the gravel less than one and one-half inches in diameter will pass through the grating or plate into the chute D and be conveyed downward to the screen apparatus, and all fragments of rocks, boulders, pebbles, 850., over one and one-half inches in diameter will slide down the upper surface of the grizzly into the lateral boulder-chute E, where it will be turned aside and fall into the waste pile.

F is a horizontal shaft journaled in a suitable framework, and this shaft is adapted to be revolved from any suitable source of power, and upon the shaft between the bearings is socured two conical-shape screens (Jr and H, one located inside of the other and a distance apart.

The inner screen is of coarser mesh than the outer screen, and the lower end of the chute D leads into the smaller end of the inner screen, and the material which has passed through the grizzly will fall by gravity into this inner revolving'screen, and all fragments of rock, pebbles, &c., smaller than threeeighths of an inch in diameter will pass through the perforations of this inner screen and fall into the outer screen, which is of thinner mesh or perforations; but all fragments of rock, pebbles, &c., larger than three-eighths of an inch in diameter will gradually work toward the larger end of the screen and be discharged from that end into a lateral chute I, which leads downward to one of the two inspection-tables J, (shown in Figs. 2 and 3,) and any gems-such as diamonds, rubies, beryls, and nuggets-if any occur in the gravel, will be spread out upon the table in the form and condition most suitable and convenient for examination.

The outer screen is substantially thirty mesh, and all of the material too large to pass through this mesh will be discharged from the larger end of this screen into a second lateral chute K and pass downward to the other of the two inspection-tables J and be spread out, as before described, for examination.

The chutes l and K are steeply inclined and have their discharging ends oppositely curved and downwardly curved in order that the material coming therefrom may pass out on a plane parallel with the plane of the table, thus insuring the distribution of the material over the surface of the said table.

L is a perforated water pipe running directly over and along the entire length of the screen and discharging water upon the screens,

said water being under Whatever pressure can be obtained.

All material passing through the outer screen H, which material is now well flooded and mixed with water, will fall into the first of a series of sluice-boxes M, each of which is arranged upon an incline one below the other in a zigzag fashion, so as to save groundspace, and this material passing out of the last sluice-box into a mercury-pocket O, and the quicksilver in this pocket will take up the fine gold and amalgamate the same, allowing the waste material to pass on through the pocket into a waste-pipe, and at the end of a days run or any timeluring the day the quicksilver containing the gold may be drawn off and the gold recovered in the usual manner.

It will thus be seen that with an extremely simple, portable, and compact device a large amount of work can be turned out in a day, as the operation of the machine need not be interrupted at any time, and this machine will run through thirty cubic yards or tons of various placer-gravel per day of ten hours, or three tons per hour, and a full percentage of all gold, coarse or fine, will be deposited in the mercury-pocket, and at the same time the precious stones and nuggets will be separated and placed on the inspection-tables by themselves.

Of course I do not wish to be limited to the exact construction here shown, as slight modifications could be made without departing from the spirit of my invention.

Having thus fully described my invention, what I claim as new and useful is- In a machine of the character described, a hopper supported in an elevated position by suitable framework, an inclined grizzly leading therefrom, in position to receive material discharging from the hopper, a chute into which the grizzly discharges, a series of conical-shaped screens suitably mounted to receive materials from the chute, an extended assortingtable suitablypositioned with relation to the screens, lateral chutes steeply inclined having their upper ends adapted to receive material from the screens and having their lower ends oppositely curved and downwardly curved, with the discharge ends extending in a direction parallel with the assorting-table, and adapted to spread the material thereover by impetus, substantially as described.

In testimony whereof I have hereunto affixed my signature in the presence of two subscribing Witnesses.

NATHANIEL WV. PULSIFER. 

